i finally got my fc up on a lift today to see what's been going on with the shakes and a gas leak.

#1: THE SHAKES

turns out the rubber seal for the transmission mount has rotted away to nothing, which then created excessive play in my driveshaft and u-joints. other rubber spots have also rotted away which need to be replaced. although this might be difficult for someone to answer without looking at it, my question is simply... are the driveshaft and u-joints pieces that can be repairable or should i just screw it and buy new ones?

#2: GAS LEAK

whoever owned my fc before i did that did the swap from non-turbo to turbo must have been an idiot (besides the fact that i've had to buy a scoop hood for it to breathe) because of this... the turbo is a standard t2, which is all well and good, until you figure in the 3" downpipe that was welded on and doesn't fit properly, creating the leak from rust and dents that have somehow come up all over it. now i'm worried... what kind of problems could arise from the wrong size downpipe being welded on to the smaller turbo? could my turbo potentially be damaged as well? i haven't noticed anything wrong with the boost, but then again, i'm used to boosting with this gas leak since i bought the car, i just didn't realize it before.

#3: NEW PARTS

i know i need to replace the downpipe with the standard t2 2.5" size, and if i need to replace the driveshaft and u-joints too, does anyone know a place where i can get a good price on all these parts?

 

i'm also wondering if it would make sense to just get a bigger turbo. any ideas?

 

Assuming the driveshaft is stock, you can replace the u-joints if you are on a budget, but it sounds relatively difficult to do. I'd just pick up a driveshaft from mazdatrix. I believe they also have the transmission mount.

 

Yeah, it's a stock driveshaft. I'm just looking to see if it is possible to actually repair the joints. They're not broken, but I believe they are bent. I'm doing more investigation on it later today. I'll look up mazdatrix too.

 

i had a set of ujoints go out on my 7 i ended up just replacing the drive shaft i looked all over for u joints and noone had them evevn the local mazda dealer as for the gas leak were is it? a line or the tank it self what is leaking?

 

yeah, that's because the driveshaft and u-joints end up going together in most cases, from what i've seen in my research. i might buy a set from mazdatrix just to get new sturdy ones. they sell them on there.

the gas leak is coming from my downpipe. it's rusted out, has a few dents, and it's the wrong size for my turbo. i don't know what the guy who owned it before me was thinking on that one.

 

You really didn't specify about the gas leak...... that can be a VERY bad thing. You need to find out where it is coming from and fix it FAST before your engine catches on fire! The culprits are obvious, check your lines, rails, injectors, and since yours is an s4, check the pulsation dampener first. In answer to your turbo question, no, you can't just go upgrading the turbocharger without supporting mods..... fuel mods, AFC, Rtek, or full standalone fuel management system, boost control, etc. without these essentials you will blow up your motor in a matter of weeks not days if you just go upgrading things. People throw on an intake, exhaust system, etc and throw on big turbo's ad hoc without thinking about things and end up running super lean, blowing up their engines and saying "rotaries suck!"..... no, they suck.

 

just read your post above me, lol. how the hell is gas leaking from your downpipe? That's not possible...... if it were then your car would be on fire by now..... fuel + hot exhaust = boom.

 

i think he means exhaust GAS leak. because the idiot that sold it to him welded a 3" pipe into his stock flange. don't worry it wont hurt the turbo, it will just stink like fuel.

 

exactly, it's an exhaust gas leak. sorry for the confusion. the odor comes up through my vents when i'm running the car, and it's pretty rank. i can't wait to get the right part and get it fixed. glad to hear the turbo should be okay! i was a little worried.

 

The u joints are not replaceable, you need to replace the driveshaft. There are people who have replaced them but that is not the recommended way to fix it.

 

Just go to a muffler shop and have them fix the leak.

Get a set of new mounts from mazdatrix, or banzai racing.